There is also a Pathfinder Spell Book app that is Free. It is pretty decent besides the occasional error (nothing of consequence) and the spells with Tables aren't easy to read. At least on a phone they aren't.

Using the PFRPG RD (payed but cheap), ifumble (cheap) and Pathfinder Spell Compendium.

PFRPG RD is a nice compendium of all open source pathfinder books, well sortet and fast loading.

Ifumbel brings a lot of fun to the table by giving "fumbel effects" if you roll a 1 (from simple "you hit the nearest target, to you crit, but your weapon breaks (also for ranged, natural and spell fumbles)

Pathfinder Spell Compendium is a spellbook where yu can choose your class, mark the spells you memorized for the day/know, including all Spell details & description. Very handy for spellcasters.

I still looking for a Hex Map Tool, where I can track the progression of my Kingmaker Campaign. :)